Portion of an electronic mouse



FIG. 1 is a front perspective view of a portion of an electronic mouse showing my new design;

FIG. 2 is a left side view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a top view thereof.

The broken line showing of a scroll wheel region is for illustrative purposes and forms no part of the claimed design. The unshown bottom of the electronic mouse forms no part of the claimed design. 

The ornamental design for a portion of an electronic mouse, as shown and described. 